Odor is that property of a substance that makes it perceptible to the sense of smell. Specifically, odor is that property that is manifested by a physiological sensation caused by contact of the molecules of a substance with the olfactory nervous system. Although molecular structure is believed to influence odor, there is little correlation, at the present time, between odor and molecular structure.
Odor modification is the intentional change of one odor by the addition of another. The importance of odor modification is its usefulness as a method of odor control. Air fresheners, perfumes, and industrial deodorants are examples of odor modifiers. Perfumers employ the principles of odor modification by creating fragrances. Thus, odor modification refers specifically to the use of fragrance materials for odor control. Many odorous and nonodorous chemicals are used to control odors, but only those that work essentially by altering the way the nose perceives the character and intensity are true odor modifiers.
A problem in the field of odor modification is in the area of perfuming bleaching compositions. Because of the inherent ability of a bleaching agent to destroy odors, it is difficult to effectively perfume a bleaching composition so that the perfume remains stable during storage and is available for effective delivery without being altered or destroyed by the bleach.
Bleaching agents are materials that lighten or whiten a substrate through chemical action. This action can involve either oxidative or reductive processes that make color bodies in the substrate more soluble and more easily removed during processing. The color producing agents in fibers are often organic compounds that contain conjugated chains, that is, alternating single and double bonds, called chromophores. Decolorization often can be achieved by destroying one or more of the double bonds in the conjugated systems such as by adding to, or cleaving, the double bond.
Bleaching agents can be classified into three catagories: chlorine containing bleaching agents, peroxygen compounds, and reducing bleaches. Three classes of chlorine-containing compounds used as bleaching agents are: chlorine, hypochlorites and N-chloro compounds, and chlorite and chlorine dioxide. The first two classes, termed available-chlorine compounds, produce hypochlorous acid and hypochlorite anion in bleaching baths. Peroxygen or active oxygen compounds contain a peroxide linkage (--O--O--) in which one oxygen atom is active, such as hydrogen peroxide. The reducing agents generally used in bleaching include sulfur dioxide, sulfurous acid, bisulfites, sulfites, hydrosulfites (dithionites), sodium formaldehyde sulfoxylate, and sodium borohydride.
U.S. Pat. No. 4,663,068 (Hagemann et al.) discloses a bleach-stable deodorant perfume stable in the presence of sodium perborate tetrahydrate and N,N,N',N'-tetraacetyl ethylenediamine. Specifically, Hagemann et al. discloses a detergent powder product suitable for use in the washing of fabrics which comprises (i) from 5 to 40% by weight of non-soap detergent active compound comprising an anionic detergent active compound; (ii) from 1 to 90% by weight of a non-soap detergency builder; (iii) from 1 to 30% by weight of peroxy bleach compound together with an activator; (iv) from 0.1 to 5% by weight of a bleach-stable perfume which comprises from 50 to 100% by weight of bleach-stable deodorant perfume components having a Lipoxidase-Inhibiting Capacity of at least 50% or a Raoult Variance Ratio of at least 1.1. The components are allocated to one of the following six classes: Class 1: Phenolic substances; Class 2: Essential oils, extracts, resins and synthetic oils; Class 3 Aldehydes and ketones; Class 4: Nitrogen-containing compounds; Class 5: Esters; Class 6: Alcohols and ethers. The components are selected so that: (a) the bleach-stable deodorant perfume contains at least five different components; and (b) the bleach-stable deodorant perfume contains components from at least four of the six classes.
U.S. Pat. No. 4,579,677 (Hooper et al.) discloses a deodorant product having a deodorant value of from 0.50 to 3.5 as measured by the Deodorant Value Test. Specifically, Hooper et al. discloses a deodorant product suitable for application to surfaces other than human skin, which product comprises (i) from 0.1 to 50% by weight of a bleaching agent; and (ii) from 0.1 to 20% by weight of a deodorant composition comprising from 45 to 100% by weight of deodorant active components, the components having a Lipoxidase-Inhibiting Capacity of at least 50% or a Raoult Variance Ratio of at least 1.1. The components are classified into the following six classes: Class 1: phenolic substances; Class 2: essential oils, extracts, resins and synthetic oils; Class 3: aldehydes and ketones; Class 4: polycyclic compounds; Class 5: esters; Class 6: alcohols. The components are selected so that (a) the deodorant composition contains at least five components of which at least one must be selected from each of Class 1, Class 2 and Class 4; and (b) the deodorant composition contains components from at least 4 of the 6 classes.